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As we age, our metabolisms and body clocks run slower, even though the sun attempts to readjust those clocks every day. Older people generally move slower than younger people do, not because they cannot move fast—they often can. They are not usually aware that their movements are slower.
When body performances (balance, reaction time, vision, hearing) slow down, the relative stride of time appears to slow down as well, so one does not notice that time has advanced at a different pace than when one was younger. For old people, time sense is adjusted to what their bodies, especially feet, are signaling to temporal components of their brains.
Oddly, some folks feel that their lives are passing faster and faster with age, yet their minute-to-minute clock seems to run slower and slower. Watch old and young folks in a supermarket. Watch how they move. Older people are subconsciously and consciously aware that they have more time, though the percentage of time remaining alive is rapidly diminishing.
Retirement has significant effects on how much time a person has on hand, but one's movement is not usually dictated by their free time. With free time comes an attitude that encourages a slowing down of motor activity. That slower pace contributes to adjustments of the internal clock that continuously tell the body how fast or how slow to move. Internal clocks tell those worn springs, gears, levers, and pistons of one's body that there is no rush to get anywhere. They confront any ponderings one might have about how much time is left before death.
Our sense of time’s perplexing flow comes from networks of inner body signals that interact with a life tuned to the natural rhythms of the world. We do, after all, have biological clocks that are regulated by cell functions, with genes turning on and off on a 24-hour cycle along with other body rhythms — heartbeat, respiration, pain, temperature, and emotion— contributing a “Gestalt” perception time.[i]
Earth rhythms influence all sorts of physiological actions that change according to times of day, the seasons, or the calendar, and even ambient temperature. They represent the circadian rhythms that tell our bodies when to sleep, when to wake, when to eat. They regulate our many physiological processes. But they also effectively modify sensations and physiological behaviors to suit the cycles of the socio-physical world.
Neurological studies tell us that receptors and transporters of the dopamine system weaken with age.[ii] Those dopamine systems are linked to an internal clock, and mechanisms that adjust temporal memory, duration discrimination, and attention.[iii] As the dopamine system weakens, internal clocks run slower. In an odd confusion, one gets the impression that life is speeding up.[iv]
Most strongly, our time senses are determined by markings of durations, such as beginnings and endings of vacations, extended travels, new situations that almost always start slowly before accelerating to an end. Our lives seem to be almost always marked by durations.
Thinking about the end of any duration of routine activity is extremely influential. A month’s vacation at a spa resort is a block of time with a beginning and end. One envisions the end as it approaches. At first, there is no routine. Meals and mealtimes are changed, sleep cycles are changed, and so is attention to time.
That block of time, with its pre-established end, plays with the mind to make time seem to pass slowly at first. Then, after a few days of that new routine, the lengths of days seem to accelerate toward the end date. Often there are biophysical changes, blood pressures, sunlight exposures, and drinking practices that complicate matters to confuse time.
We know that we’re not here on Earth for very long. Proximity to the end of life is instrumental to the reason why we think time speeds up with age. It is the body’s vigilant signal of the coming of that last good night, the weary cell’s cautionary warning of the impending expiration date, the end-date of our longest block of time. We know that day is coming, but not when.
As we age, we become more and more aware of the “when” as our aging cells become increasingly lax and confused about coordinated functions, such as when in the circadian cadence to turn protein building on and off. Also, we learn of more and more deaths of friends and relatives to find life more and more ephemeral than we once thought.
The mind, then, attempts to snub forever-increasing background dins that whisper whims about the number of years left. Eventually, we all come to an age when the cells of our body tell us that the years seem to be going by fast, and that next year will seem shorter than this one.
With age, we tend to focus more and more on the longest duration of all, that last good night.
© 2020 Joseph Mazur
References
[i] Marc Wittmann, Translated by Erik Butler, Felt Time: The Psychology of How We Perceive Time (Cambridge, Massachusetts: 2106) 132-134.
[ii] Jean-Claude Dreher, et al. (March 3, 2008) “Age-related changes in midbrain dopaminergic regulation of the human reward system,” Proceedings of the National Academy of Sciences of the US, Vol. 105, No. 39, 15106-15111.
[iii] Warren H. Meck, (June 1996) “Neuropharmacology of timing and time perception,” Cognitive Brain Research, Vol. 3, Issues 3-4, pp. 227-242.
[iv] Mangan, P.A. Bolinskey, P.K. and Rutherford, A.L. Wolfe, C. (1996). “Altered time perception in elderly humans results from the slowing of an internal clock.” Society for Neuroscience Abstracts, 221-3): 183.
